Offensive by Ukrainian Military Results in Gains; Rebels, Government Agree on Cease-Fire

The Ukrainian military began an aggressive campaign in early July, using airstrikes to back up ground troops. The military forced rebels from the towns of Sloviansk, their military headquarters, and Kramatorsk; surrounded Donetsk, the largest city in eastern Ukraine; and took control of some of the border crossings through which Russia had been arming the rebels. The offensive was not without cost: by the end of July, about 1,130 people had been killed, including about 800 civilians. Russia responded by massing about 20,000 troops on the border with Ukraine.

The rebels continued to struggle into August, as government troops moved into Luhansk and Donetsk, former rebel strongholds. In addition, many rebels were reported to have abandoned the fight. Two days after Poroshenko and Putin met to discuss options to end the conflict, NATO, citing satellite images, reported that Russia sent 1,000 troops into Ukraine from the southeast, opening a new front in the conflict. Russia has long denied it had dispatched troops to Ukraine, and said the troops entered Ukraine "accidentally."

"Over the past two weeks we have noted a significant escalation in both the level and sophistication of Russia's military interference in Ukraine," said NATO's Brig. Gen. Nico Tak in a statement released in late August.

On September 5, representatives from the Ukrainian government, the Russian-backed separatists, Russia, and the Organization for Security and Cooperation in Europe who had been meeting in Minsk, Belarus, announced that they had agreed on a ceasefire. The terms include an immediate end to fighting, the exchange of prisoners, amnesty for those who did not commit serious crimes, a 6-mile buffer zone along the Ukrainian-Russian border, decentralization of power in the Donbass region (the area dominated by the Russian-backed rebels), and the creation of a route to deliver humanitarian aid. It also said local elections will be held under terms of Ukrainian law. "The whole world is striving for peace, the whole of Ukraine is striving for peace, including millions of citizens in Donbass," Poroshenko said in a statement. "The highest value is human life, and we must do everything possible to stop the bloodshed and put an end to suffering." Despite the cease-fire, both sides continued to attack each other.

On September 16, Ukraine's parliament and the European Parliament ratified the EU Association Agreement—the deal that former President Yanukovich refused to sign, sparking the protests that led to Yanukovich's ouster. The agreement will not be fully implemented until the end of 2015, leaving some concerned that it will be watered down by the time it's in place. Ukraine's parliament also voted to give the rebel-controlled areas of the Donbas region increased autonomy and self-governance and maintain Russian language rights for three years. It also granted amnesty to rebel fighters.